QUESTION:
Given an integer num, return the number of digits in num that divide num.
An integer val divides nums if nums % val == 0.
Example 1:
Input: num = 7
Output: 1
Explanation: 7 divides itself, hence the answer is 1.
Example 2:
Input: num = 121
Output: 2
Explanation: 121 is divisible by 1, but not 2. Since 1 occurs twice as a digit, we return 2.
Example 3:
Input: num = 1248
Output: 4
Explanation: 1248 is divisible by all of its digits, hence the answer is 4.
Constraints:
1 <= num <= 109
num does not contain 0 as one of its digits.
EXPLANATION:
easy的题目, 直接除即可.
SOLUTION:
class Solution {
func countDigits(_ num: Int) -> Int {
var count = 0
var mutableNum = num
while mutableNum % 10 != 0 {
let digit = mutableNum % 10
if num % digit == 0 {
count += 1
}
mutableNum /= 10
}
return count
}
}